Enabling and disabling a PageBlockSection in Salesforce

Enabling and disabling a PageBlockSection in Salesforce

Sample code:

Visualforce page:

<apex:page controller="Sample" >
<apex:form >

<apex:pageblock id="pg" >
    <apex:pageblockSection columns="1" title="PBS1" rendered="{!pbs1}"  >
        <apex:pageblocksectionItem >
            <apex:inputCheckbox value="{!pbs1cb1}">
                <apex:actionSupport event="onchange" action="{!check}" reRender="pg"/>
            </apex:inputCheckbox>
        </apex:pageblocksectionItem>
        <apex:pageblocksectionItem >
            <apex:inputCheckbox value="{!pbs1cb2}">
                <apex:actionSupport event="onchange" action="{!check}" reRender="pg"/>
            </apex:inputCheckbox>       
        </apex:pageblocksectionItem>
        <apex:pageblocksectionItem >
            <apex:inputCheckbox value="{!pbs1cb3}">
                <apex:actionSupport event="onchange" action="{!check}" reRender="pg"/>
            </apex:inputCheckbox>       
        </apex:pageblocksectionItem>               
    </apex:pageblockSection>             

    <apex:pageblockSection columns="1" title="PBS2" rendered="{!pbs2}"  >
        <apex:pageblocksectionItem >
            <apex:inputCheckbox value="{!pbs2cb1}">
                <apex:actionSupport event="onchange" action="{!check}" reRender="pg"/>
            </apex:inputCheckbox>
        </apex:pageblocksectionItem>
        <apex:pageblocksectionItem >
            <apex:inputCheckbox value="{!pbs2cb2}">
                <apex:actionSupport event="onchange" action="{!check}" reRender="pg"/>
            </apex:inputCheckbox>       
        </apex:pageblocksectionItem>
        <apex:pageblocksectionItem >
            <apex:inputCheckbox value="{!pbs2cb3}">
                <apex:actionSupport event="onchange" action="{!check}" reRender="pg"/>
            </apex:inputCheckbox>       
        </apex:pageblocksectionItem>               
    </apex:pageblockSection> 

    <apex:pageblockSection columns="1" title="PBS3" rendered="{!pbs3}"  >
        <apex:pageblocksectionItem >
            <apex:inputCheckbox value="{!pbs3cb1}">
                <apex:actionSupport event="onchange" action="{!check}" reRender="pg"/>
            </apex:inputCheckbox>
        </apex:pageblocksectionItem>
        <apex:pageblocksectionItem >
            <apex:inputCheckbox value="{!pbs3cb2}">
                <apex:actionSupport event="onchange" action="{!check}" reRender="pg"/>
            </apex:inputCheckbox>       
        </apex:pageblocksectionItem>
        <apex:pageblocksectionItem >
            <apex:inputCheckbox value="{!pbs3cb3}">
                <apex:actionSupport event="onchange" action="{!check}" reRender="pg"/>
            </apex:inputCheckbox>       
        </apex:pageblocksectionItem>               
    </apex:pageblockSection>

</apex:pageblock>

</apex:form>
</apex:page>

Apex Controller:

public class Sample
{
    public Boolean pbs1cb1 {get;set;}
    public Boolean pbs1cb2 {get;set;}
    public Boolean pbs1cb3 {get;set;}
   
    public Boolean pbs2cb1 {get;set;}
    public Boolean pbs2cb2 {get;set;}
    public Boolean pbs2cb3 {get;set;}
   
    public Boolean pbs3cb1 {get;set;}
    public Boolean pbs3cb2 {get;set;}
    public Boolean pbs3cb3 {get;set;}   
   
    public Boolean pbs1 {get;set;}
    public Boolean pbs2 {get;set;}   
    public Boolean pbs3 {get;set;}  
   
    public sample()
    {
        pbs1 = true;
        pbs2 = false;
        pbs3 = false;
    }

    public void check()
    {
        if(pbs1cb1 == true && pbs1cb2 == true && pbs1cb3 == true)
        {
            pbs2 = true;
           
            if(pbs2cb1 == true && pbs2cb2 == true && pbs2cb3 == true)
            {
                pbs3 = true;
            }
            else
            {
                pbs3 = false;
            }
        }
        else
        {
            pbs2 = false;
            pbs3 = false;
        }
    }
}

Ouput: